//
// (C) Copyright 2009 Irantha Suwandarathna (irantha@gmail.com)
// All rights reserved.
//

/* Copyright (c) 1995-2000, The Hypersonic SQL Group.
 * All rights reserved.
 *
 * Redistribution and use _in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions _in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer _in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the Hypersonic SQL Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE HYPERSONIC SQL GROUP,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * on behalf of the Hypersonic SQL Group.
 *
 *
 * For work added by the HSQL Development Group:
 *
 * Copyright (c) 2001-2008, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use _in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions _in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer _in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


using System;


namespace EffiProz.Core.Lib
{

    public class Sort
    {

        /**
         * FastQSorts the [l,r] partition (inclusive) of the specfied array of
         * Rows, using the comparator.
         *
         * Modified from the original method _in Hypersonic with the addition of
         * the comparator. (fredt@users)
         *
         * @author Thomas Mueller (Hypersonic SQL Group)
         * @version 1.7.2
         * @since 1.7.2
         */
        public static void sort(Object[] w, ObjectComparator comparator,
                                      int l, int r)
        {

            int i;
            int j;
            Object p;

            if (l > r)
            {
                return;
            }

            while (r - l > 10)
            {
                i = (int)((uint)(r + l)) >> 1;

                if (comparator.compare(w[l], w[r]) > 0)
                {
                    swap(w, l, r);
                }

                if (comparator.compare(w[i], w[l]) < 0)
                {
                    swap(w, l, i);
                }
                else if (comparator.compare(w[i], w[r]) > 0)
                {
                    swap(w, i, r);
                }

                j = r - 1;

                swap(w, i, j);

                p = w[j];
                i = l;

                while (true)
                {
                    while (comparator.compare(w[++i], p) < 0)
                    {
                        ;
                    }

                    while (comparator.compare(w[--j], p) > 0)
                    {
                        ;
                    }

                    if (i >= j)
                    {
                        break;
                    }

                    swap(w, i, j);
                }

                swap(w, i, r - 1);
                sort(w, comparator, l, i - 1);

                l = i + 1;
            }

            for (i = l + 1; i <= r; i++)
            {
                Object t = w[i];

                for (j = i - 1; j >= l && comparator.compare(w[j], t) > 0; j--)
                {
                    w[j + 1] = w[j];
                }

                w[j + 1] = t;
            }
        }

        /**
         * Swaps the a'th and b'th elements of the specified RowAVL array.
         */
        private static void swap(Object[] w, int a, int b)
        {

            Object t = w[a];

            w[a] = w[b];
            w[b] = t;
        }
    }
}
